Tire with belt between bias carcass plies

ABSTRACT

A bias ply tire incorporates a pair of oppositely oriented nonwoven breakers between two successive body plies in the region underlying the crown region of the tread layer. The breakers are inserted prior to shaping and curing. In a four-ply tire, one such pair of breakers preferably is inserted between the first and second, that is, the innermost, body plies, and another such pair of breakers may similarly be inserted between the third and fourth, that is, the outermost, body plies. Also, a third such pair of breakers may be inserted between the second and third body plies if further improved results are desired. The cord directions of each successive layer, whether a body ply or a breaker, may alternate relative to the longitudinal center line of the tire crown or the cords of successive coacting layers of breaker and body ply may be in the same general direction relative to the longitudinal center line of the tire crown. The result is an improvement in stability, owing to a lower cord angle in the crown region, without any sacrifice of ride softness, owing to a higher cord angle in the sidewall region.

United States Patent [191 Jennings et a1.

[451 Dec. 25, 1973 TIRE WITH BELT BETWEEN BIAS CARCASS PLIES both ofMich.

[73] Assignee: Uniroyal Inc., New York, NY.

[22] Filed: Dec. 17, 1970 [21] Appl. No.: 99,109

Related [1.8. Application Data [63] Continuation-impart of Ser. No.793,299, Jan. 23,

1969, abandoned.

[52] US. CL... 152/356, 152/D1G. 19 [51] Int. Cl. ..B6.0c 9/20 [58]Field of Search 152/354, 356, 361

[56] References Cited UNITED STATES PATENTS 1,181,540 5/1916 Peaslee152/361 X 3,068,926 12/1962 Jacob et a1 152/354 1,374,957 4/1921 Seaton152/348 2,930,425 3/1960 Lugli et a1 152/361 X FOREIGN PATENTS ORAPPLICATIONS 1,554,424 1/1969 France 152/354 Primary Examiner-Gerald M.Forlenza Assistant Examiner-George H. Libman Attorney-Charles A. Blank[5 7 ABSTRACT A bias ply tire incorporates a pair of oppositely orientednon-woven breakers between two successive body plies in the regionunderlying the crown region of the tread layer. The breakers areinserted prior to shaping and curing. In a four-ply tire, one such pairof breakers preferably is inserted between the first and second, thatis, the innermost, body plies, and another such pair of breakers maysimilarly be inserted between the third and fourth, that is, theoutermost, body plies. Also, a third such pair of breakers may beinserted between the second and third body plies if further improvedresults are desired. The cord directions of each successive layer,whether a body ply or a breaker, may alternate relative to thelongitudinal center line of the tire crown or the cords of successivecoacting layers of breaker and body ply may be in the same generaldirection relative to the longitudinal center line of the tire crown.The result is an improvement in stability, owing to a lower cord anglein the crown region, without any sacrifice of ride softness, owing to ahigher cord angle in the sidewall region.

24 Claims, 7 Drawing Figures PATENIEUmzs m5 3.780.782 SHEET 1 or 6 \QF'V"KQ'QQ' George J Jeni)! 6' Par/751V. [W610 S g & l 14 arrow "MENTEUUEE25m5 3,780,782 swan 2 UF 6 INVENTORS 6096: 4. c/ewwms PAWS Ma mmrgnnsczs192s 3.780.782

SHEET 5 BF 6 g INVENTOR.

GEORGE L.JENNINGS BY PARKS M.NIGHOLS This application is acontinuation-in-part of our copending application, Ser. No. 793,299,filed Jan. 23, 1969, entitled Bias Ply-Tire, and now abandoned.

This invention relates to pneumatic tires for automotive vehicles, andis particularly applicable to the bias ply type of tire construction.

Among the objectives of automotive tire design is an improved stabilityof the tire without sacrificing ride softness. A softer ride increasespassenger comfort, while improved stability contributes to more preciseand safer control of the vehicle, and also causes the tire to run coolerand wear less rapidly. The prior art has recognized that, in a bias plytire, the way to achieve a softer ride is to have a higher cord angle inthe sidewalls, and the, way to improve stability is to have a lower cordangle in the crown region. The difficulty has been that until now, noone has found a practical way to make the cord angle lower in the crownand higher in the sidewalls simultaneously than in a conventional tireto which the cosine law is applicable as will be discussed subsequently.Accordingly, in the past there has always been a tradeoff betweencomfort and stability in the design of a tire.

Breakers have been used in the construction of tires for quite sometime. Generally these were disposed immediately beneath the crown of thetire, between the tread layer and the outermost carcass ply. When soplaced, breakers have a tendency to separate from the carcass plies atthe breaker edges, particularly in severe service. In some cases theprior art appears to have experimented with the insertion of a singlebreaker between the carcass plies of a bias ply tire, but without anyknown improvement in ride softness or stability. Pairs of oppositelyoriented breakers have also been placed between the carcass plies ofradial ply tires, but the radial ply type of tire construction isinherently incapable of developing improved riding qualities or greaterstability from such breaker placement.

Among the objects of the invention are to provide a tire which ridessoftly and atire which is more stable. In particular, it is an object ofthe invention to achieve a softly riding tire and a greater stability inthe same tire at the same time. Additional objects are to provide longertire wear, cooler running temperatures, and greater resistance toseparation at the breaker edges.

In accordance with the invention and contrary to the conventional beliefof the tire industry, it is possible to achieve a lower crown cord angleand a higher sidewall cord angle simultaneously in a bias ply tire. Thissurprising result has been achieved by a tire structure including meansbetween the carcass plies which, during the shaping and curing of thetire body, interact with the carcass plies in such a way that theresulting cured cord angles are lower in the crown region and higher inthe sidewall region than the cosine law predicts.

In conventional tire constructions, wherein the breakers are exterior tothe carcass plies, the resultant shaped cord angles of the plies areprogressively lower in each successive ply. That is, the first orinnermost carcass ply has the highest cord angle and the outermostbreaker ply has the lowest cord angle. The normal pantographic actionbetween adjacent plies during shaping and curing is free to follow theprinciples of the cosine law due to the absence of interacting breakers.

The resultant shaped cord angles in one form of the tire in accordancewith the invention are essentially the same in similar components. Thecord angles of all the breakers are equal (but opposite) and the cordangles in the crown region of all the associated carcass plies are equal(but opposite). Also, the shaped cord angles in the sidewall portions ofthe carcass plies are equal (but opposite).

In specific forms of the invention, the interacting means is a pair ofbreakers inserted between two adjacent carcass plies. The corddirections of successive plies and breakers may or may not bealternating. In

'manufacturing the tire of the invention, first one bias ply is disposedon the building drum on which a suitable air-impervious liner may havebeen previously disposed, then a first breaker, a second breaker, and asecond bias ply are applied in accordance with the invention withsuccessive breakers in oppositely disposed relationship. After shapingand curing, it is found that the interaction of the two interposedbreakers with the surrounding body plies produces a lower than expectedcarcass cord angle in the crown and a higher than expected carcass cordangle in the sidewall. As a result, a soft ride and greater stabilityare obtained simultaneously.

FIG. 1 is a cutaway perspective view of a portion of a finished two-plybias tire in accordance with this invention.

FIG. 2 is a cutaway perspective view of a portion of a finished four-plybias tire in accordance with the invention.

FIG. 3 is a graph showing the cord angle distribution achieved by meansof this invention, compared with the distribution predicted by thecosine law.

FIG. 4 is a plan view, with parts broken away, of a tire tread layer andcarcass, in accordance with the invention on a building drum.

FIG. 5 is a cutaway perspective view of a portion of a finished two-plybias tire made in accordance with a preferred form of the invention.

FIG. 6 is a plan view, with parts broken away, of a tire tread layer andcarcass on a building drum in accordance with a preferred form of theinvention as shown in FIG. 5.

FIG. 7 is a cutaway perspective view of a portion of a finished four-plybias tire in accordance with a preferred form of the invention.

The same reference characters and the same reference characters primedrefer to corresponding elements throughout the several views of thedrawings.

The tire of FIG. 1 is similar in some respects to a conventional two-plytire employing the bias ply type of contruction which is popular in theindustry. This tire comprises a body 12 of generally toroidalconfiguration. The periphery of the toroid comprises a tread layer 14 inwhich are molded grooves 16. t

A pair of curved sidewalls 18 extend radially from the shoulders 20 ofthe tread layer 14 and terminate in bead assemblies 22 which are adaptedto engage the rim of a wheel. The beads 22 are reinforced by steel wires24 running longitudinally therethrough, and processed in the usualmanner with a rubbery material 26.

The sidewalls l8 incorporate a pair of carcass plies 30 and 32, whichmay be formed of nylon or rayon cords, or other suitable materials,combined into sheet form with a rubbery material by conventional methodssuch as calendering. Additional layers of material 34 and 36 form theouter and inner surfaces respectively of each sidewall 18.

Thus, the body plies 30 and 32 extend substantially continuously overone sidewall 18, across the crown of the tread layer 14, and over theother sidewall 18. The plies also encompass the beads 22 at theextremities of each sidewall.

FIG. 1 shows the individual cords employed in the carcass plies 30 and32. As is usual in a bias-ply tire, the cord directions of the plies 30and 32 are opposed. That is, if an observer looks in the directionindicated by the arrow 40 along the longitudinal center line of thetread layer 14, the direction of the cords of ply 32 slants to the leftacross that center line, as indicated by arrow 42, while the cords ofply 30 slant to the right relative to that line, as indicated by arrow44. The angle between arrows 42 and 40 is the cord angle for ply 32, andsimilarly the angle between arrows 44 and 40 is the cord angle for ply30. I

In the manufacture of a conventional tire the plies 30 and .32ordinarily are laid flat upon a drum with their respective cordsoriented in the opposite directions indicated by arrows 42 and 44. In atypical instance, the cord angle is, for example, 64.5" relative to areference line which subsequently becomes the longitudinal center lineof the tread layer 14. Subsequently, the carcass plies 30 and 32 arecurved downwardly from the region of the crown of the tread layer 14 toform the two sidewalls 18, while the tire is shaped into a toroid andsubsequently cured in a manner conventional in the industry.

Referring to a conventional tire without breakers, it is known thatafter shaping and curing, the cord angles will no longer'be the same aswhen the carcass plies and 32 were initially placed upon the drum. Theshaped angle is substantially everywhere less than the building angle.The exact value of the shaped angle varies, being lowest at the centerof the tread layer 14, and somewhat higher at the region of the beads22, but still not as high as the building angle. Between its extremevalues, the shaped angle varies smoothly as a function of distance fromthe longitudinal center line, according to a mathematical relationshipknown as the cosine law, which is illustrated by trace 50 in the graphofFIG. 3.

The cosine law is widely known in the tire industry as an equation forpredicting the cord angle in a bias ply tire from crown angle tosidewall angle. As indicated in the publication Tire Engineering andDevelopment by Johnson available at the University of Akron, Akron,Ohio, the cosine law may be expressed:

Cos ca= Cos ba X S/] +E where ca represents the cured cord crown angle(or cured sidewall angle) at each pont from the crown center,

ba represents the fabric bias angle,

S represents the expansion ratio of the plies, at each point from thecrown center, from a tire on a flat drum to a shaped tire,

E represents per cent elongation of the cords (cord stretch) Theexpansion ratio measured from a point on the flat built tire to a pointon the shaped and cured tire varies from the region of the crown to theregion of the bead and thus the angle ca varies as the measurementproceeds around the tire.

Trace 50 of FIG. 3 was derived by making actual measurements of a curedtire of conventional constructron.

Inspection of trace 50 of FIG. 3 reveals that the reduction in cordangle from the built to the shaped state- ,an effect known aspantographing, pulls the cord angle below the built value in thesidewall region. Such a reduction of the sidewall cord angle undesirablyreduces the softness of the ride provided by the tire. It wouldtherefore be desirable to limit the reduction in the sidewall cord anglewhich occurs during shaping.

Trace 50 also reveals that the cosine law distribution results in aneven larger decrease in the cord angle in the crown region.Nevertheless, for the sake of improved stability, it is desirable forthe cured angle in the crown region to be reduced still further.

In accordance with the present invention, both of these objectives havebeen achieved, specifically by means involving a novel distribution ofbreakers. A breaker is a layer of material, usually non-woven andcomprising cords of nylon, rayon, steel or other suitable material,conventionally calendered with a rubbery compound and applied entirelyaround the tire, and underlying the tread layer 14. Breakers usuallyextend only'slightly or not at all into the sidewalls 18. Such beakersare normally interposed between the tread and the outermost carcass ply,to lend additional stability to the tire.

Contrary to conventional practice, the breaker is omitted between thetread layer and the outermost carcass ply 30 of the tire constructed inaccordance with the invention. Moreover, two breakers 52 and 54 arelocated between carcass plies 30 and 32. While the prior art hasexperimented with a single breaker between bias body plies, it has notsuggested the advantages of a pair of breakers such as 52 and 54 in thatparticular location in a bias ply tire.

In FIG. 1 the direction of the cords of breakers 52 and 54 are indicatedby arrows 56 and 58, respectively. It is apparent that the cords of thetwo breakers 52 and 54 slant in opposite directions relative to thelongitudinal center line of the tread layer 14; arrow 56 slanting to theleft, and arrow 58 slanting to the right. In addition, it should benoted that the cord directions of the successive layers 30, 52, 54 and32 are in alternating relationship. That is, the cords of carcass ply 30slant to the right (arrow 44), the cords of breaker 52 immediately belowit slant to the left (arrow 56), the cords of the next succeeding layer,breaker 54, slant to the right (arrow 58), and finally the cords of thenext succeeding layer, carcass ply 32, slant to the left, (arrow 42),all with reference to the longitudinal center line of tread layer 14,and as seen by an observer looking along that center line in thedirection indicated by arrow 40.

It has been found that because the cord angle of the breakers is lowerthan the cord angle of the adjacent carcass plies, the breakersexaggerate the pantographing of the carcass plies in the tread region,and since the carcass ply ends are fixed at the heads, the tendency ofthe carcass plies to pantograph in the sidewall region is minimized.Also, the fact that, not one, but two breakers 52 and 54 are locatedbetween the carcass plies 30 and 32, plus the fact that the corddirection of each breaker may be in opposed or unopposed relationship tothe cord direction of its adjacent carcass ply and its adjacent breaker,produces an interaction between the cords of the carcass plies andbreakers during shaping, and this interaction causes the cured cordangles to vary from the cosine law distribution. A frictional force isexerted by the different slanting cords of breaker 52 upon the slantingcords of carcass ply 30, and a similar force is exerted by the differentslanting cords of breaker 54 upon the slanting cords of carcass ply 32,which restricts them from assuming the orientation which would normallybe expected. Moreover, breakers 52 and 54 interact with each other.

, This theory is supported by the observation that prior art placementof a pair of cross-oriented breakers between the carcass plies of aradial ply tire, and of a single breaker between the carcass plies of abias ply tire,

did not produce the angle changes and the improvement in stabilitywithout loss of ride softness achieved by this invention.

In manufacturing the tire according to one form of this invention, thebottom carcass ply 32 is laid flat on the drum over the liner, then thebottom breaker 54 is laid thereover in opposed relationship, the topbreaker 52 follows in opposed relationship to the breaker 54, andfinally the top carcass ply 30 is applied over the breaker 52 in opposedrelationship to ply 32. Thus, in ascending order from the drum, the corddirections of the layers 32, 54, 52 and 30 slant left, right, left,right as indicated by arrows 42, 58, 56 and 44, respectively.

In accordance with this invention, the building cord angles at which thebreakers 52 and 54 are applied over the drum are somewhat lower thanthose of the carcass plies 30 and 32. Experimentation with thisdifferential between the building cord angles indicates that a value ofup to about is open to consideration. However, the largest practicalangle differential seems to be about 8, without risking separation ofadjacent carcass layers at the breaker edges, and probably it ispreferable to use a differential in the range from 3 to 5. In a specificexample where the carcass plies 30 and 32 were laid down on the drum atbuilding cord .angles of 645 relative to the reference line, adifferential of 8 between the breaker angles and the carcass ply angleswas employed. Accordingly, the building cord angle at which the breakers52 and 54 were applied to the drum was 56.5 relative to the referenceline.

The introduction of such a cord angle differential between the breakers52, 54 and the carcass plies 30, 32, with the breakers having the lowercord angle, aids the interaction between these layers as they areincorporated into a tire structure. While angledifferentials up to 15have been used successfully, it has been experienced that angledifferentials of approximately half the magnitude are more desirable.When such an angle differential is employed, and the breaker edgesextend in stepped off relation to the proximity of the shoulders 20, theresultant tire is more resistant to separation of the adjacent layers insevere service.

Referring now to one form of the invention shown in FIG. 4, the tirebody 12 is represented on a building drum with tread layer, breakers,and plies being partly broken away so that the cord angles may be seen.The breakers and plies have been broken away along the lines designatingthe angles of the cords. As represented in the drawing, the outermostply 30 has a cord angle of 645. The breaker 52 has a cord angle of 56.5which is opposition to the cord angle of the outermost ply 30. Thebreaker 54 has a cord angle of 56.5 which is in opposition to the cordangle of the breaker 52. The

- tions from the cosine law. In FIG. 3, trace 32-1 shows the shaped cordangle distribution for the bottom carcass ply 32, while trace 30-1 showsthe corresponding data for the top carcass ply 30, and traces 54-1 and52-1 show the shaped cord angle distributions for the breakers 54 and52, respectively.

The breaker cord angles are reduced from their building value of 56.5 toshaped values ranging from 23 to 24 (at the longitudinal center line ofthe tread 14) up to 25 to 26 (near the edges of the breakers 52 and 54,i.e., near the shoulders 20). This large differential between thebuilding and shaped cord angles for the breakers 52 and 54 indicatesthat a powerful force has been exerted upon the breaker cords duringshapmg.

As for the shaped cord angles of the carcass plies themselves, traces30-1 and 32-1 show that these angles are depressed below the valuespredicted by the cosine law trace 50, in thelower part of the graphwhich represents the crown region of the tread layer 14. This lowercrown angle in the tread region produces a substantial improvement inthe stability of the tire. At the same time, the shaped cord angle inthe upper portion of the graph, representing the region of the sidewalls18, is seen to be everywhere greater than the values indicated by thecosine law trace 50. As a result, the tire achieves softness of itsride. To recapitulate, the present invention succeeds in achieving alower crown angle at the same time that it achieves a higher sidewallangle. As a result, stability is improved without sacrificing softnessof the ride.

The present invention is also applicable to four-ply bias tires. As seenin FIG. 2, a bias tire of the kind described herein may comprise, inaddition of the carcass plies 30 and 32, an additional pair of carcassplies 60 and 62. In that case, an additional pair of breakers 64 and 66may be provided between the two additional carcass plies.

In manufacturing a four-ply tire in accordance with one embodiment ofthis invention, the bottom carcass ply 32 is first laid down on the drumover a liner previously disposed thereon, followed by breaker 54,breaker 52 and carcass ply 30, for example, at angles similar to theangles of corresponding members of the FIG. 1 tire while the carcass ofthe FIG. 1 tire is on the drum. Then the previously discussed carcassply 62, breaker 66, breaker 64 and the topmost carcass ply 60 areapplied thereover in that order, for example, at angles similar to theangles of carcass ply 32, breaker 54, breaker 52, and carcass ply 30,respectively, of the FIG. 1 tire while the carcass of the FIG. 1 tire ison the drum. The tire is subsequently shaped and cured in theconventional manner. Once again, no breaker is placed in theconventional location between the tread layer and carcass ply 30.

The cords of the additional carcass plies 60 and 62 and the additionalbreakers 64 and 66, shown in FIG. 2, function in a similar manner tocarcass plies 30 and 32 and breakers 52 and 54 as previously described.Specifically, the cords of' the carcass. ply 62 may slant in thedirection shown (arrow 70), the next succeeding layer, breaker 66, mayslant oppositely (arrow 72), the next succeeding layer, breaker 64,slants oppositely to breaker 66 (arrow 74), and the next succeedinglayer, carcass ply 60, slants oppositely to carcass ply 62 (arrow 76).

The pattern of left, right alternation of succeeding layers may becarried out through all the layers 32, 54, 52, 30, 62, 66, 64, 60 of thetire carcass. This promotes interaction between opposed cords throughoutthe tire.

If further improvement is desired, a third pair' of breakers, similar tobreakers 64 and 66, may be disposed between plies 30 and 62 of the FIG.2 embodiment with breaker cord angles and slant of cords selected in amanner similar to that previously described in connection with the FIG.2 embodiment. That is, the breaker in contact with ply 30 may have aslanted cord direction in opposition to the cord direction of ply 30,and the breaker in contact with ply 62 may have a slanted cord directionin opposition to the cord direction of ply 62.

If only one pair of breakers is used in a four-ply tire, it may bepositioned between any two carcass plies to provide greater stabilitytogether with softness of ride than is provided by a corresponding tirewithout a breaker.

In accordance with a preferred form of the invention shown in FIG. 5,the FIG. 5 tire is a two-ply tire generally similar to the FIG. 1 tireexceptthat, for example, the cords of breaker 52' slant to the right andthe cords of breaker 54' slant to the left. As represented in FIG. 6,the building cord angles of the carcass plies 30' and 32 are preferabl635 relative to the longitudinal center line of the tread layer. Thedirections of the cords of breakers 52, 54', of FIG. 6 are reversed withrespect to the longitudinal center line of the tread layer as comparedwith the cords of breakers 52, 54 of FIG. 4. The building cord angles ofbreakers 52', 54' are preferably 57.5 relative to the longitudinalcenter line of the tread layer. Thus, the cord directions of adjacentcarcass plies of FIG. 5 and 6 slant oppositely to each other relative tothe longitudinal center line of the tread layer and the cord directionsof the breakers slant oppositely to'each other relative to thelongitudinal center line of the tread layer. The cords of each breakerslant in the same general direction as the cords of each carcass plyadjacent thereto relative to the lontials in the ranges stated above forthe building cord angles of tires with opposed or unopposed breaker andadjacent carcass ply angular relationships.

The FIG. 7 tire is a four-ply tire having a first pair of plies andfirst pair of breakers applied to a drum, for example, at angles similarto angles of corresponding gitudinal center line of the tread layer. Inthe FIG. 5 tire 1 the angle of the cords of the carcass plies relativeto the longitudinal center line of the tread layer is less in the regionof the center line than the angle predicted in that region by the cosinelaw. The angle of the cords of the carcass plies relative to thelongitudinal center line of the tread layer is greater in the sidewallregion than the angle predicted for the sidewall region by the cosineIaw.

As represented in FIG. 6, the building cord angles at which the breakers52' and 54' are applied over the drum are somewhat lower than those ofthe carcass plies 30 and 32'. It is believed that values of the angledifferential of up to about 15 may be used, while about 5 to about 8 isthe preferred range of values and about 2 is believed to be the minimumuseful angle differential. The more compliant materials selected for thebreakers and carcass plies can ordinarily be used with higher angledifferentials while the less compliant materials are ordinarily usefulwith lower angle differenmembers of the FIG. 5 tire while the FIG. 5tire is on the drum and utilizing an additional pair of breakers betweenthe two additional carcass plies. The second pair of carcass plies andthe second pair of breakers are applied to a drum, of example, at anglessimilar to the angles of the first pair of carcass plies and first pairof breakers of the FIG. 5 tire while the carcass of the FIG. 5 tire ison the drum.

While specific examples of two-ply and four-ply tires constructed inaccordance with the invention have been described herein, tires havingmore than two plies may be constructed in accordance with the inventionby utilizing the principles described herein to position at least a pairof breakers between selected carcass plies.

While there have been described what are at present believed to be thepreferred embodiments of the invention, it will be obvious to thoseskilled in the art that various changes and modifications may be madetherein without departing from the invention, and, it is therefore,aimed to cover all such changes and modifications as fall within thetrue spirit and scope of the invention.

We claim:

1. A bias ply tire having crown and sidewall regions comprising:

a tread layer;

and a bias ply carcass including at least a pair of beads and at leasttwo carcass plies extending from bead to bead, each of said carcassplies having cords oriented in a respective direction at an acute anglerelative to the longitudinal center line of said tread layer, said anglebeing greater in the sidewall region than in the crown region of thetire;

said carcass also including at least a pair of breakers having cords andbeing in overlaid relation and in direct contact with eachother and withthe adjacent carcass plies and both breakers disposed, in the regionunderlying said tread layer, between a pair of said carcass plies whichare separated from each other only by at least one of said breakers overthe entire area of said breakers.

2. A tire in accordance with claim 1, wherein:

each of said breakers has cords oriented in a respective direction;

said breakers being positioned with their cord directions opposed toeach other.

3. A tire in accordance with claim 1, wherein:

each of said carcass plies has cords oriented in a respective direction;

said carcass plies being positioned with their cord directions at acuteangles to the longitudinal center line of said tread layer, and opposedto each other.

4. A tire in accordance withclaim 2, wherein: said breakers arepositioned with their cord directions opposed to each other and at acuteangles relative to the longitudinal centerline of said tread layer. l i5. A tire in accordance with claim 1, wherein:

each of said carcass plies has cords oriented in a respective directionat an acute angle relative to the longitudinal center line of said treadlayer;

each of said breakers has cords oriented in a respective direction at anacute angle relative to said longitudinal center line of said treadlayer;

and the cord directions of each successive carcass ply and breaker slantoppositely to the cord directions of each adjacent carcass ply andbreaker in alternating directions relative to said longitudinal centerline of said tread layer through all of said carcass plies and breakers.

6. A tire in accordance with claim 5, wherein:

said cord angles of said carcass plies are greater than said cord anglesof said breakers relative to said longitudinal center line of said treadlayer.

7. A tire in accordance with claim 5, wherein:

said tread layer is disposed directly in contact with the outermost oneof said carcass plies.

8. A tire in accordance with claim in which said angle of said cords ofsaid carcass plies relative to said longitudinal center line of saidtread layer is less in the region of said center line than the anglepredicted in that region by the cosine law.

9. A tire in accordance with claim 5 having a sidewall region in whichsaid angle of said cords of said carcass plies relative to saidlongitudinal center line of said tread layer is greater in said sidewallregion of the angle predicted for said sidewall region by the cosinelaw.

10. A tire in accordance with claim 8 having a sidewall region in whichsaid angle of said cords of said carcass plies relative to saidlongitudinal center line of said tread layer is greater in said sidewallregion than the angle predicted for said sidewall region by the cosinelaw.

11. A tire in accordance with claim 1, wherein:

each of said carcass plies has cords oriented in a respective directionat an acute angle relative to the longitudinal center line of said treadlayer;

each of said breakers has cords oriented in a respective direction at anacute angle relative to said longitudinal center line of said treadlayer;

and the cord directions of said adjacent carcass plies slant oppositelyto each other relative to said longitudinal center line of said treadlayer and the cord directions of each pair of breakers slant oppositelyto each other relative to said longitudinal center line of said treadlayer.

12. A tire in accordance with claim 11, wherein:

said cords of each breaker slant in the same general direction as saidcords of each carcass ply adjacent thereto relative to said longitudinalcenter line of said tread layer.

13. A tire in accordance with claim 11 in which said angle of said cordsof said carcass plies relative to said longitudinal center line of saidtread layer is less in the region of said center line than the anglepredicted in that region by the cosine law.

14. A tire in accordance with claim 11 having a sidewall region in whichsaid angle of said cords of said carcass plies relative to saidlongitudinal center line of said tread layer is greater in said sidewallregion than the angle predicted for said sidewall region by the cosinelaw.

15. A tire in accordance with claim 13 having a sidewall region in whichsaid angle of said cords of said carcass plies relative to saidlongitudinal center line of said tread layer is greater in said sidewallregion than the angle predicted for said sidewall region by the cosinelaw.

16. A bias ply tire having crown and sidewall regions comprising:

a tread layer;

and a bias ply carcass including a pair of beads and two pairs ofcarcass plies extending from bead to bead, each of said carcass plieshaving cords oriented in a respective direction at an acute anglerelative to the longitudinal center line of said tread layer, said anglebeing greater in the sidewall region than in the crown region of thetire;

said carcass also including two pairs of breakers having cords;

the outermost pair of said carcass plies underlying said tread layer andhaving a first pair of said breakers in overlaid relation and in directcontact with each other and with the adjacent carcass plies of saidoutermost pair and both breakers of said first pair being disposed, inthe region underlying said tread layer, between said outermost pair ofsaid carcass plies which are separated from each other only by at leastone of said breakers of said first pair over the entire area of saidbreakers of said first pair;

the innermost pair of said carcass plies underlying said outermost pairand having a second pair of breakers in overlaid relation and in directcontact with each other and with-the adjacent carcass plies of saidinnermost pair and both breakers of said second pair being disposed, inthe region underlying said tread layer, between said innermost pair ofsaid carcass plies which are separated from each other only by at leastone of said breakers of said second pair over the entire area of saidbreakers of said second pair.

17. As an intermediate article of manufacture, an unshaped, uncureddrum-built bias ply tire body comprising:

a tread layer;

and a bias ply carcass of approximately cylindrical shape including atleast a pair of beads approximately at the edges of the cylinder and atleast two carcass plies extending from bead to bead, each of saidcarcass plies having cords oriented in a respective direction at anacute angle relative to the longi-. tudinal center line of said treadlayer;

said carcass also including at least a pair of breakers having cords andbeing in overlaid relation and in direct contact with each other andwith the adjacent carcass plies and both breakers disposed, in theregion underlying said tread layer, between a pair of said carcass plieswhich are separated from each other only by at least one of saidbreakers over the entire area of said breakers; upon shaping said tirebody into a tire having crown and sidewall regions, said acute angle ofsaid cords of each of said carcass plies being greater in the sidewallregion than in the crown region of the tire.

18. As an intermediate article of manufacture, a tire body in accordancewith claim 17, wherein:

each of said carcass plies has cords oriented in a respective direction;

said carcass plies being positioned with their cord directions at acuteangles to the longitudinal center line of said tread layer;

each of said breakers has cords oriented in a respective direction; saidbreakers being positioned with their cord directions opposed to eachother and at acute angles relative to the longitudinal center line ofsaid tread layer. 19. As an intermediate article of manufacture, a tirebody in accordance with claim 18, wherein:

said angles of said carcass plies are larger than said angles of saidbreakers by a maximum differential of approximately fifteen degrees. 20.As an intermediate article of manufacture, a tire body in accordancewith claim 18, wherein: said angles of said carcass plies are largerthan said angles of said breakers by a maximum differential ofapproximately eight degrees. 21. As an intermediate article ofmanufacture, a tire body in accordance with claim 18, wherein:

said angles of said carcass plies are larger than said angles of saidbreakers by a minimum differential of approximately three degrees. 22.As an intermediate article of manufacture, a tire body in accordancewith claim 17, wherein:

each of said carcass plies has cords oriented in a respective directionat an acute angle relative to the longitudinal center line of said treadlayer;

each of said breakers has cords oriented in a respective direction at anacute angle relative to the longitudinal center line of said treadlayer;

and the cord directions of said adjacent carcass plies slant oppositelyto each other relative to said longitudinal center line of said treadlayer and the cord directions of each pair of breakers slant oppositelyto each other relative to said longitudinal center line of said treadlayer.

23. As an intermediate article of manufacture, a tire body in accordancewith claim 22, wherein:

said cords of each breaker slant in the same general direction as saidcords of each carcass ply adjacent thereto relative to said longitudinalcenter line of said tread layer.

24. A bias belted pneumatic tire comprising a carcass including a pairof beads, a pair of carcass plies of tire cord fabric extendingcircumferentially of the tire and between the beads, and with additionalplies disposed between the pair of carcass plies consisting of a paironly of superposed belt plies of tire cord fabric with each belt plybeing in intimate contact with the belt ply and carcass ply nextadjacent thereto.

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@fiTEEQA'EE @QMQQTEEN hunt Ne. 378 Q 782 mime December 5, 1973 avatar)George Lo Jennings and Parks M, Nichols It 1e cmiifieei we: ewes?egzgmme in she ebwwidmtifiad patent and that @8165 Mmem Emema em hewbyeeweemsi as; ehmm Miran Column 5 line 26 fer makers xr'ead breakerwnColumn 9, line 28, far '9? fihan e Cancel claim 12?,

Cancel claim 250 On the cover sheet, after the AbS'tT.C'Z ""24 Claims"should read Z2 Ci'aims Signed and sealed this day 0f Octcber 1974.

(SEAL) Attest:

MCCOY M, GIBSON JR}, Co ZLRSHALL .DANN

Attesting Officer Gemiesiener 15 Patents

1. A bias ply tire having crown and sidewall regions comprising: a treadlayer; and a bias ply carcass including at least a pair of beadS and atleast two carcass plies extending from bead to bead, each of saidcarcass plies having cords oriented in a respective direction at anacute angle relative to the longitudinal center line of said treadlayer, said angle being greater in the sidewall region than in the crownregion of the tire; said carcass also including at least a pair ofbreakers having cords and being in overlaid relation and in directcontact with each other and with the adjacent carcass plies and bothbreakers disposed, in the region underlying said tread layer, between apair of said carcass plies which are separated from each other only byat least one of said breakers over the entire area of said breakers. 2.A tire in accordance with claim 1, wherein: each of said breakers hascords oriented in a respective direction; said breakers being positionedwith their cord directions opposed to each other.
 3. A tire inaccordance with claim 1, wherein: each of said carcass plies has cordsoriented in a respective direction; said carcass plies being positionedwith their cord directions at acute angles to the longitudinal centerline of said tread layer, and opposed to each other.
 4. A tire inaccordance with claim 2, wherein: said breakers are positioned withtheir cord directions opposed to each other and at acute angles relativeto the longitudinal center line of said tread layer.
 5. A tire inaccordance with claim 1, wherein: each of said carcass plies has cordsoriented in a respective direction at an acute angle relative to thelongitudinal center line of said tread layer; each of said breakers hascords oriented in a respective direction at an acute angle relative tosaid longitudinal center line of said tread layer; and the corddirections of each successive carcass ply and breaker slant oppositelyto the cord directions of each adjacent carcass ply and breaker inalternating directions relative to said longitudinal center line of saidtread layer through all of said carcass plies and breakers.
 6. A tire inaccordance with claim 5, wherein: said cord angles of said carcass pliesare greater than said cord angles of said breakers relative to saidlongitudinal center line of said tread layer.
 7. A tire in accordancewith claim 5, wherein: said tread layer is disposed directly in contactwith the outermost one of said carcass plies.
 8. A tire in accordancewith claim 5 in which said angle of said cords of said carcass pliesrelative to said longitudinal center line of said tread layer is less inthe region of said center line than the angle predicted in that regionby the cosine law.
 9. A tire in accordance with claim 5 having asidewall region in which said angle of said cords of said carcass pliesrelative to said longitudinal center line of said tread layer is greaterin said sidewall region of the angle predicted for said sidewall regionby the cosine law.
 10. A tire in accordance with claim 8 having asidewall region in which said angle of said cords of said carcass pliesrelative to said longitudinal center line of said tread layer is greaterin said sidewall region than the angle predicted for said sidewallregion by the cosine law.
 11. A tire in accordance with claim 1,wherein: each of said carcass plies has cords oriented in a respectivedirection at an acute angle relative to the longitudinal center line ofsaid tread layer; each of said breakers has cords oriented in arespective direction at an acute angle relative to said longitudinalcenter line of said tread layer; and the cord directions of saidadjacent carcass plies slant oppositely to each other relative to saidlongitudinal center line of said tread layer and the cord directions ofeach pair of breakers slant oppositely to each other relative to saidlongitudinal center line of said tread layer.
 12. A tire in accordancewith claim 11, wherein: said cords of each breaker slant in the samegeneral direction as said cords of each carcass ply adjacent theretorelative to said longitudinal center line of said tread layer.
 13. Atire in accordance with claim 11 in which said angle of said cords ofsaid carcass plies relative to said longitudinal center line of saidtread layer is less in the region of said center line than the anglepredicted in that region by the cosine law.
 14. A tire in accordancewith claim 11 having a sidewall region in which said angle of said cordsof said carcass plies relative to said longitudinal center line of saidtread layer is greater in said sidewall region than the angle predictedfor said sidewall region by the cosine law.
 15. A tire in accordancewith claim 13 having a sidewall region in which said angle of said cordsof said carcass plies relative to said longitudinal center line of saidtread layer is greater in said sidewall region than the angle predictedfor said sidewall region by the cosine law.
 16. A bias ply tire havingcrown and sidewall regions comprising: a tread layer; and a bias plycarcass including a pair of beads and two pairs of carcass pliesextending from bead to bead, each of said carcass plies having cordsoriented in a respective direction at an acute angle relative to thelongitudinal center line of said tread layer, said angle being greaterin the sidewall region than in the crown region of the tire; saidcarcass also including two pairs of breakers having cords; the outermostpair of said carcass plies underlying said tread layer and having afirst pair of said breakers in overlaid relation and in direct contactwith each other and with the adjacent carcass plies of said outermostpair and both breakers of said first pair being disposed, in the regionunderlying said tread layer, between said outermost pair of said carcassplies which are separated from each other only by at least one of saidbreakers of said first pair over the entire area of said breakers ofsaid first pair; the innermost pair of said carcass plies underlyingsaid outermost pair and having a second pair of breakers in overlaidrelation and in direct contact with each other and with the adjacentcarcass plies of said innermost pair and both breakers of said secondpair being disposed, in the region underlying said tread layer, betweensaid innermost pair of said carcass plies which are separated from eachother only by at least one of said breakers of said second pair over theentire area of said breakers of said second pair.
 17. As an intermediatearticle of manufacture, an unshaped, uncured drum-built bias ply tirebody comprising: a tread layer; and a bias ply carcass of approximatelycylindrical shape including at least a pair of beads approximately atthe edges of the cylinder and at least two carcass plies extending frombead to bead, each of said carcass plies having cords oriented in arespective direction at an acute angle relative to the longitudinalcenter line of said tread layer; said carcass also including at least apair of breakers having cords and being in overlaid relation and indirect contact with each other and with the adjacent carcass plies andboth breakers disposed, in the region underlying said tread layer,between a pair of said carcass plies which are separated from each otheronly by at least one of said breakers over the entire area of saidbreakers; upon shaping said tire body into a tire having crown andsidewall regions, said acute angle of said cords of each of said carcassplies being greater in the sidewall region than in the crown region ofthe tire.
 18. As an intermediate article of manufacture, a tire body inaccordance with claim 17, wherein: each of said carcass plies has cordsoriented in a respective direction; said carcass plies being positionedwith their cord directions at acute angles to the longitudinal centerline of said tread layer; each of said breakers has cords oriented in arespective direction; said breakers being positioned with their corddirections opposed to each other and at acute angles relative to thelongitudinal center line of said tread layer.
 19. As an intermediatearticle of manufacture, a tire body in accordance with claim 18,wherein: said angles of said carcass plies are larger than said anglesof said breakers by a maximum differential of approximately fifteendegrees.
 20. As an intermediate article of manufacture, a tire body inaccordance with claim 18, wherein: said angles of said carcass plies arelarger than said angles of said breakers by a maximum differential ofapproximately eight degrees.
 21. As an intermediate article ofmanufacture, a tire body in accordance with claim 18, wherein: saidangles of said carcass plies are larger than said angles of saidbreakers by a minimum differential of approximately three degrees. 22.As an intermediate article of manufacture, a tire body in accordancewith claim 17, wherein: each of said carcass plies has cords oriented ina respective direction at an acute angle relative to the longitudinalcenter line of said tread layer; each of said breakers has cordsoriented in a respective direction at an acute angle relative to thelongitudinal center line of said tread layer; and the cord directions ofsaid adjacent carcass plies slant oppositely to each other relative tosaid longitudinal center line of said tread layer and the corddirections of each pair of breakers slant oppositely to each otherrelative to said longitudinal center line of said tread layer.
 23. As anintermediate article of manufacture, a tire body in accordance withclaim 22, wherein: said cords of each breaker slant in the same generaldirection as said cords of each carcass ply adjacent thereto relative tosaid longitudinal center line of said tread layer.
 24. A bias beltedpneumatic tire comprising a carcass including a pair of beads, a pair ofcarcass plies of tire cord fabric extending circumferentially of thetire and between the beads, and with additional plies disposed betweenthe pair of carcass plies consisting of a pair only of superposed beltplies of tire cord fabric with each belt ply being in intimate contactwith the belt ply and carcass ply next adjacent thereto.